Various systems and methods for fabricating awning structures and frames for fabric covered structures are known. Some of these methods use various shapes of extrusions for the frame structure, in combination with the stapling of the fabric covering material within a generally U-shaped channel in the extrusion and the covering of the staple channel with an extruded pliable component. This method results in a relatively light and water tight securing means for the fabric, so long as that fabric is in a continuous sheet and secured to a single extruded frame member.
A problem arises when a larger structure must be constructed and two or more sheets of fabric material or the like must be used to cover the entire structure, and/or two or more sections of extrusion must be joined. Again, several methods may be used, such as welding the various frame members together and sewing sections of fabric together. While these methods are reasonably durable, they do possess disadvantages for use in the field.
Most welding is done in the shop, since proper equipment is more accessible there. Since most fabric framing structures are aluminum, special electrical welding equipment (Heliarc, TIG--Tungsten Inert Gas--or the like) is generally used rather than more easily portable oxyacetylene equipment which is normally used for steel structures. Such portable electrical welding equipment is of course available, but is bulkier and less portable than oxyacetylene equipment. Obviously, for larger jobs it is necessary to perform such electrical welding operations in the field at the construction site rather than in the shop, necessitating the carriage of special electrical welding equipment to the job site and the provision of electrical power for the welding equipment.
While other mechanical connecting systems are known, problems exist in providing a light and water tight seal when two or more sections of fabric are conjoined at that point. In at least one other system, a specially shaped pliable covering extrusion must be used to seal the joint between two parallel structural members. This results in an unsightly seam, since the joint seal does not match the other extruded pliable channel covering used along other frame members.
Sewed seams present other problems. Unless the measurements are absolutely precise, it is unlikely that a seam will fall exactly within the staple channel of a framing extrusion. This will result in an unsightly seam which may admit water and light through the thread holes. In addition, the thread used may well deteriorate after being exposed to sunlight and weather for a period of time, resulting in the requirement for major repairs on the fabric covering.
Other techniques are used to eliminate the sewing requirement. Generally, any fabric used is cut so as to be joined within the staple channel of an extrusion and is merely stapled in place with the conjoining section of fabric. However, systems other than the present invention are generally sized so as to cause difficulty in inserting the nose of a staple gun or an extruded pliable channel covering when more than one layer of fabric is used.
The need arises for a system and method of joining two or more fabric framing structure members and two or more overlying fabric covering sheets, which will provide a joint or seam which is uniform in appearance with other joints or seams in other areas of the structure. The method should provide a joint or seam which is both light and water tight. The method should permit easy assembly in the field with relatively simple hand tools or battery powered portable electrical tools, thus eliminating the need for transporting relatively heavy and/or bulky specialized equipment to the job site and the need for a source of electrical power.